<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script>
        let a = 5;
        switch (a) {
            // 使用 === 比较
            case 1:
            case 3:
            case 5:
                console.log("大月31天");
                break;
            case 2:
                console.log("小月29天");
                break;
            case 4:
                console.log("小月30天");
                break;

            default:
                console.log('不合法的数字');
                break;
        }
        // console.log("1" == 1)
        // console.log("1" === 1)
    </script>
</head>
<body>

</body>
</html>
